MTech II sm

Service Manual – Preliminary Version
MCQUAY MicroTech II Control
pLAN+Driver
for Modular Chillers
McQuay ALS / WHS / PFS
With screw compressors, 1 to 4 circuits
Release of the Manual: 1.0 - 01/05/2001
Service Manual – Preliminary Version
MicroTech II Control
Contents
APPLICATIONS AND FUNCTIONS CARRIED OUT BY THE SYSTEM...........................................................................................3
MASTER/SLAVE SYSTEM ARCHITECTURE.................................................................................................................................4
INPUT/OUTPUT LIST.....................................................................................................................................................................5
AIR/WATER UNIT WITH MAX. 4 SCREW COMPRESSORS MCQUAY ALS / WHS ....................................................................................5
WATER/WATER UNIT WITH MAX. 2 SCREW COMPRESSORS, MCQUAY PFS .......................................................................................6
REGULATION................................................................................................................................................................................7
OUTLET TEMPERATURE REGULATION ...............................................................................................................................................7
CONTINUOUS UNLOADING ...............................................................................................................................................................7
Principles of working: ...........................................................................................................................................................7
Forced Unloading..................................................................................................................................................................10
START-UP OF A SINGLE COMPRESSOR ............................................................................................................................................11
Description of the logic : ........................................................................................................................................................11
START OF THE COMPRESSOR MOTOR .............................................................................................................................................12
Description of the Logic: ........................................................................................................................................................12
LIMITATIONS AT COMPRESSOR START.............................................................................................................................................12
PUMPDOWN................................................................................................................................................................................13
COMPRESSOR ROTATION .............................................................................................................................................................14
CONDENSATION REGULATION........................................................................................................................................................15
CONDENSATION CONTROL WITH CUT ENABLING .......................................................................................................................................16
MicroTech II Reference .........................................................................................................................................................16
Description............................................................................................................................................................................16
ANTIFREEZE REGULATION.............................................................................................................................................................17
ELECTRO-VALVE MANAGEMENT ....................................................................................................................................................18
Working Description ..............................................................................................................................................................18
WATER PRESSURE CONTROL FOR PFS UNITS .................................................................................................................................20
CONTROL LOGIC OF THE COOLING TOWER FOR PFS ........................................................................................................................22
PFS with single compressor:...................................................................................................................................................22
PFS with two Compressors: ....................................................................................................................................................23
CONTROL LOGIC OF THE 3-WAY VALVE FOR PFS UNITS....................................................................................................................23
ALARMS......................................................................................................................................................................................24
GENERAL DESCRIPTION................................................................................................................................................................24
ALARM HISTORICAL......................................................................................................................................................................24
ALARM TABLE .............................................................................................................................................................................25
DRIVER ALARMS ..........................................................................................................................................................................26
PLAN NETWORK.........................................................................................................................................................................27
I/O card address....................................................................................................................................................................27
Terminal address...................................................................................................................................................................28
TERMINAL MANAGEMENT ..............................................................................................................................................................28
Terminal configuration procedure...........................................................................................................................................29
Display of the terminal connection state .................................................................................................................................30
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Service Manual – Preliminary Version
MicroTech II Control
Applications and functions carried out by the system
Type of controlled units
air / water only chiller
air / water chiller + heat pump
Compressor maximum number
Max. 1 compressor for MicroTech II card, with max. 4 MicroTech II card capacity controls
Compressor type
Screw compressors
Compressor call rotation
Rotation of all the compressors with FIFO logic
Electronic expansion valve management (EXV)
Management of the EX7 and EX8 Alco valve.
Safety for each refrigeration circuit
High pressure (pressure switch)
Low pressure (pressure switch)
Oil differential pressure switch
Compressor thermal
Condensation fan thermal
High Discharge Temperature on the compressor
Phase Monitor
Star / Delta Transition Failed
Low Delta Pressure between Suction and Discharge
System security
A serious alarm input (stops the whole unit) , available both in the MASTER and SLAVE unit
A flow controller input (stops the whole unit) , available both in the MASTER and SLAVE unit
A pump thermal input (stops the whole unit)
Remote on/off input without alarm signaling
Regulation type
Proportional or proportional + integral regulation on the evaporator input probe.
Condensation
The condensation can be carried out according to temperature or pressure
The fans can be managed according to ON/OFF mode
Or with a 0/10 V modulating signal
Accessories
Supervision with RS422/RS485 serial card.
EVD driver backup EVBAT battery module.
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Service Manual – Preliminary Version
MicroTech II Control
Master/slave system architecture
The system is composed of at least two up to four MicroTech IIs connected to the local network of which the first acts as master and the following
act as slaves.
Master function
Temperature regulation
All compressor call
Manages the system alarms
Management of a refrigeration circuit (start, stop, alarms, EXV)
Communication possibility with an external supervisor
Slave function
Management of a refrigeration circuit (start, stop, alarms, EXV) for each card
Common functions
Both master and slave manage (configuration and regulation) max 2 EVD drivers and consequently max 2 EXV valve each.
Regulation probe
The thermo-regulation probe have to be connected only to the master MicroTech II.
Thermoregulation of the
whole system
MicroTech II MicroTech II
1
2
(Master)
(Slave)
EXV 1
EXV 2
EXV 3
EXV 4
Driver 1
Driver 2
Driver 3
Driver 4
Terminal
LCD (4x20)
Each MicroTech II card, driver card and terminal are identified with an address. The terminal address is selected via the dip-switches situated on
the back of the terminals themselves whereas the address in he I/O cards is always selected via dipswitches placed on a card with MICROTECH
IIADR0000 code (without clock option) or MICROTECH IICLKMEM0 (with clock option); this card has to be inserted in the clock plug-in connector.
The address dip-switches of the EVD driver are on the back of the front-cover (removable) of the driver itself.
The master MicroTech II must have address 1
The MicroTech II slave must have address 2
The driver 1 must have address 3
The driver 2 must have address 4
The driver 3 must have address 5
The driver 4 must have address 6
The local terminal must have address 8
Note : when the unit is ON, all the MicroTech II cards and the drivers must be ON (LED On/Off on the terminal ON for all the units).
•
•
•
The master unit starts/stops all the units
The slave unit starts/stops itself only. If the slave unit is OFF and master is ON, the slave does not starts. If the slave is ON and t
master is OFF, the slave does not start.
The drivers have no start enabling (are always ON : this does not mean that the driver begins immediately to control because, as
long as the MicroTech II units do not cause at least one compressor to start, the driver continues to receive a 0% request and
consequently the valve is kept closed).
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Service Manual – Preliminary Version
MicroTech II Control
Input/output list
Below the inputs and outputs are listed as a function of the unit type; a number has been associated to each type of machine. This number is the
principal parameter of the program as it identifies the input and output configuration. In this way the configuration of the machine is made very easy
because you need only choose the requested input and output list and select the associated number in the program configuration masks. Each of
the following pages contains 2 unit types and for each unit the MicroTech II inputs/outputs from master and the inputs/outputs of one of the slave
MicroTech IIs are described.
AIR/WATER Unit with max. 4 screw compressors McQuay ALS / WHS
Digital inputs
Only Chiller unit
MACHINE TYPE “0”
N
UNIT 1(Master)
UNIT 2 (Slave n. 1)
UNIT 3 (Slave n. 2)
UNIT 4 (Slave n. 3)
1
2
3
4
5
6
7
8
9
10
11
12
On/Off by Main Switch
Evaporator flow controller (enabling)
Remote On/Off
Oil Level 1
Low pressure pressure switch 1
Oil differential 1 (I series only)
Phase Monitor (enabling)
Double Setpoint
Fan thermal 1 circ 1
Failed trans. Y/∆
High pressure pressure switch 1
Comp.thermal 1
On/Off by Main Switch
Evaporator flow controller (enabling)
N.U.
Oil Level 2
Low pressure pressure switch 3
Oil differential 2 (I series only)
Phase Monitor (enabling)
N.U.
Fan thermal 1 circ 2
Failed trans. Y/∆
High pressure pressure switch 2
Comp.thermal 2
On/Off by Main Switch
Evaporator flow controller (enabling)
N.U.
Oil Level 3
Low pressure pressure switch 1
Oil differential 3 (I series only)
Phase Monitor (enabling)
N.U.
Fan thermal 1 circ 3
Failed trans. Y/∆
High pressure pressure switch 3
Comp.thermal 3
On/Off by Main Switch
Evaporator flow controller (enabling)
N.U.
Oil Level 4
Low pressure pressure switch 3
Oil differential 4 (I series only)
Phase Monitor (enabling)
N.U.
Fan thermal 1 circ 4
Failed trans. Y/∆
High pressure pressure switch 4
Comp. thermal 4
Analog inputs
Only Chiller unit
n
UNIT 1(Master)
UNIT 2 (Slave n. 1)
UNIT 3 (Slave n. 2)
UNIT 4 (Slave n. 3)
1
2
3
4
5
6
7
8
Entering water temp.
Leaving water Temp.
Cir1 LiqTmpALS / InCnd.Tmp.WHS
Comp.1 Oil Temp
Oil Diff Transducer Circ 1
Setpoint Reset Override
Circuit 1 High pressure transducer
Compr Capacity Sensor Circ 1
N.U.
Outlet Cond. Temperature (WHS)
Cir2 LiqTmpALS / InCnd.Tmp.WHS
Comp.2 Oil Temp
Oil Diff Transducer Circ 2
Demand Limit Signal/ Voltage/Amps
Circuit 2 high pressure transducer
Compr Capacity Sensor Circ 2
N.U.
N.U.
Cir3 LiqTmpALS / InCnd.Tmp.WHS
Comp.3 Oil Temp
Oil Diff Transducer Circ 3
N.U.
Circuit 3 high pressure transducer
Compr Capacity Sensor Circ 3
N.U.
N.U.
Cir4 LiqTmpALS / InCnd.Tmp.WHS
Comp.4 Oil Temp
Oil Diff Transducer Circ 4
N.U.
Circuit 4 high pressure transducer
Compr Capacity Sensor Circ 4
Digital outputs
Only Chiller unit
N
UNIT 1(Master)
UNIT 2 (Slave n. 1)
UNIT 3 (Slave n. 2)
UNIT 4 (Slave n. 3)
1
2
3
4
5
6
7
8
9
10
11
12
13
Circulation pump
Line Contactor comp. 1
Star Contactor comp. 1
Delta Contactor comp.1
N.U.
Unloader 1 comp.1 C.
Unloader 2 comp.1 S.
Circuit 1 condens. Fan 3
Liquid Inj. 1
Antifreeze heater
General alarm cumulat.
Circuit 1 condens. Fan 1
Circuit 1 condens. Fan 2
N.U.
Line Contactor comp..2
Star Contactor comp. 2
Delta Contactor comp..2
N.U.
Unloader 1 comp.2 C.
Unloader 2 comp.2 S.
Circuit 2 condens. Fan 3
Liquid Inj. 2
N.U.
General alarm cumulat.
Circuit 2 condens. Fan 1
Circuit 2 condens. Fan 2
N.U.
Line Contactor comp. 3
Star Contactor comp..3
Delta Contactor comp.3
N.U.
Unloader 1 comp.3 C.
Unloader 2 comp.3 S.
Circuit 3 condens. Fan 3
Liquid Inj. 3
N.U.
General alarm cumulat.
Circuit 3 condens. Fan 1
Circuit 3 condens. Fan 2
N.U.
Line Contactor comp..4
Star Contactor comp. 4
Delta Contactor comp.4
N.U.
Unloader 1 comp.4 C.
Unloader 2 comp.4 S.
Circuit 4 condens. Fan 3
Liquid Inj. 4
N.U.
General alarm cumulat.
Circuit 4 condens. Fan 1
Circuit 4 condens. Fan 2
Analog outputs
Only Chiller unit
n
UNIT 1(Master)
UNIT 2 (Slave n. 1)
UNIT 3 (Slave n. 2)
UNIT 4 (Slave n. 3)
1
2
Condens. fan-speed reg. 2
N.U.
Condens. fan-speed reg. 3
N.U.
Condens. fan-speed reg. 4
N.U.
Condens. fan-speed reg. 1
N.U.
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Service Manual – Preliminary Version
MicroTech II Control
WATER/WATER Unit with max. 2 screw compressors, McQuay PFS
Digital inputs
Only Chiller unit
MACHINE TYPE “3”
N
UNIT 1(Master)
UNIT 2 (Slave)
1
2
3
4
5
6
7
8
9
10
11
12
On/Off by Main Switch
Evaporator flow controller (enabling)
Remote On/Off
Oil Level 1
Low pressure switch 1
Oil differential 1
Phase Monitor (enabling)
Double Setpoint
N.U.
Failed trans. Y/∆
High pressure switch 1
Comp.thermal 1
On/Off by Main Switch
Evaporator flow controller (enabling)
N.U.
Oil Level 2
Low pressure switch 2
Oil differential 2
Phase Monitor (enabling)
N.U.
N.U.
Failed trans. Y/∆
High pressure switch 2
Comp.thermal 2
Analog inputs
Only Chiller unit
n
UNIT 1(Master)
UNIT 2 (Slave)
1
2
3
4
5
6
7
8
Entering water temp.
Leaving water temp.
Liquid Temperature Circ 1 (opt.)
Comp.1 Oil Temp
Oil Diff Transducer Circ 1
Setpoint Reset Override
High pressure transducer
Compr Capacity Sensor circ 1
Ent. condens. temp.
Outlet Condenser Temperature
Liquid Temperature Circ 2 (opt.)
Comp.2 Oil Temp
Oil Diff Transducer Circ 2
Demand Limit Signal
Voltage/Amps
Compr Capacity Sensor circ 2
Digital outputs
Only Chiller unit
N
UNIT 1(Master)
UNIT 2 (Slave)
1
2
3
4
5
6
7
8
9
10
11
12
13
Circulation pump
Line Contactor comp. 1
Star Contactor comp. 1
Delta Contactor comp.1
N.U.
Unloader 1 comp.1 C.
Unloader 2 comp.1 S.
Circuit 1 condens. Tower fan 3
Liquid Inj. 1
N.U.
General alarm cumulat.
Circuit 1 condens. Tower fan 1
Circuit 1 condens. Tower fan 2
N.U.
Line Contactor comp..2
Star Contactor comp. 2
Delta Contactor comp..2
N.U.
Unloader 1 comp.2 C.
Unloader 2 comp.2 S.
Circuit 2 condens. Tower fan 3
Liquid Inj. 2
N.U.
General alarm cumulat.
Circuit 2 condens. Tower fan 1
Circuit 2 condens. Tower fan 2
Analog outputs
Only Chiller unit
n
UNIT 1(Master)
UNIT 2 (Slave)
1
2
Condens. Tower fan-speed reg. 2
N.U.
Condens. Tower fan-speed reg. 1
N.U.
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Service Manual – Preliminary Version
MicroTech II Control
Regulation
Outlet temperature regulation
CONTINUOUS UNLOADING
Used Inputs:
• Inlet Temperature
• Outlet Temperature
Used Parameters:
• Regulation Setpoint
• Outlet temperature Regulation Band
• Continuous unloading Dead Band
Dead-band
• Pulse Period
• Minimum Pulse Time for solenoid 1
• Maximum Pulse Time for solenoid 1
• Minimum Pulse Time for solenoid 2
• Maximum Pulse Time for solenoid 2
• Enabling to continuous power ramp-up
• Time of forced ON for solenoids before compressor start-up
Used outputs:
• Digital Output n°6 for solenoid 1
• Digital Output n°7 for solenoid 2
Principles of working:
Continuous unloading uses 2 solenoids to control screw compressor slide and thus its capacity, control is performed by outlet temperature.
Logic of solenoids is selectable by mask, the following table shows the default configuration:
SOLENOID A
OFF
OFF
fixed OFF
ON (pulsating)
SOLENOID B
fixed ON
ON (pulsating)
fixed OFF
ON (pulsating)
COMPRESSOR BEHAVIOR
Compressor just started o in forced power decrease
Floating power decrease
Dead band with system in pause
Floating power increase
ON fixed = solenoid is always ON (not pulsating)
OFF fixed = solenoid is always OFF (not pulsating)
ON = solenoid floats with a trend toward the state of ON fixed
OFF = solenoid floats with a trend toward the state of OFF fixed
In the graphic is sketched the mode of working of the unload solenoids.
Slide moves by pulses of increasing or decreasing time, depending on the system is in the zone of increasing or decreasing power.
The only data to be inserted by the user is the Dead Band inside the Outlet temperature Regulation Band, all remaining thresholds will be
calculated automatically by the software.
Outlet temperature Regulation Band
Pulse Time
Stop comp with
dead-band reg
A
Release 1.0 01/05/01
Floating decrease
B
(setpoint)
Dead band
C
Floating increase
D
E
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Service Manual – Preliminary Version
MicroTech II Control
Logic of the Continuous unloading through the points of the graphic :
Compressors will start when temperature will be higher than the upper end of the neutral zone ( Setpoint + band).
Consequently compressors will start after point E, and increasing pulses will have the maximal duration.
At compressors start discharge is forced for a selectable time.
Temperature higher than point E (compressor start):
Compressor start is controlled by the values of outlet water temperature, they start in sequence with a selectable interstage requested to reach the
full power, increasing power by pulses of maximal duration. After this time compressor is assumed at the top of the power, consequently each
device will continue to work at the reached power.
Temperature between D and E (zone of floating increase):
In that temperature band only the last compressor started will float in increase of power, for an infinite time, unless it reaches full conditions. The
remaining compressors keep working on the reached power value. Modulation pulses will have variable duration based on the temperature.
Temperature between D and C (neutral zone):
In the neutral zone logic remain in stand-by and all compressors keep working on the reached power value.
Temperature between C and B (zone of floating decrease) :
• With compressors rotation: all compressors go in stand-by except for the first started, starting to float in decrease with pulses of
duration increasing with the temperature decrease.
• Without compressors rotation: all compressors go in stand-by except for the last started starting to float in decrease with pulses of
duration increasing with the temperature decrease.
Temperature under point B (compressors shutdown):
When temperature falls down point B (regulation Setpoint) compressors start floating in decrease with pulses of maximal duration, the real
shutdown arrives after a selectable interstage to assume compressor is arrived at minimum power.
Description of the Logic based on Temperature (models without capacity sensor)
•
On temperature increase : When outlet temperature exceeds point E, the first compressor is starter, floating in increase with maximal pulse
duration. Assumed temperature keeps over point E, increase will continue for a selected time, until we can consider compressor at full capacity.
At this point the second compressor will be requested to start, and it will work as described; while the first one will keep working in steady
configuration (in theory at 100%). If temperature remains over point E, step by step all compressors will follow in the same way.
•
On temperature decrease : Assume all compressors working and at full capacity. When outlet temperature falls down to the zone of floating
increase, since compressors are at full capacity, further power increase is impossible.
If temperature keeps falling down it will reach the neutral zone where compressors will maintain a stable working.
Falling down again it will reach the zone of floating decrease.
Here starts floating in decrease the first or the last compressor started, based on the rotation. Decrease phase will continue for a time
selectable until we can consider compressor at zero capacity, next it will be shut down and a phase of decrease will start for a new compressor.
If temperature will remain in that zone all compressors will be shut down in the same way.
•
Special Cases :
(a) Assume the temperature is over the point E and one compressor is in phase of increase. If temperature falls down to the zone of
floating increase, the compressor still not arrived at full capacity will continue increasing its power with a duration of pulses now
variable instead of fixed. If temperature continues falling down it will arrive to the neutral zone, where all compressors will work in
steady mode, next to the zone of floating decrease where compressor with partial capacity will start decrease. When stopped, one
by one the remaining compressors will shut down as described.
(b) Assume the temperature is in the zone of floating decrease, and one compressor is in phase of decrease. If temperature goes up
suddenly over point E, that compressor will start decreasing, even if it has needed before to reach the maximal power.
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Service Manual – Preliminary Version
MicroTech II Control
In program masks will be selectable :
• Output Setpoint of the regulation (User Menu) è Point B
• Temperature Band for output regulation (User Menu) è between B and E
• Neutral Band to control continuous unloading (User Menu) è between C and D
• Solenoid Configuration for the phase of stand-by
• Solenoid Configuration for the phase of increase
• Solenoid Configuration for the of decrease
• Period pulses (Manufacturer Menu).
• Max and Min Duration of pulses on solenoids 1 and 2 (Manufacturer Menu).
• Time of forced ON of solenoids at compressor start. (Manufacturer Menu)
Duration
Of the pulse
Pulse Period
Pulse period
Pulse period
MASTER card controls the effective start and stop of the compressors and the rotation by the ordinary regulation in output; the handling of the
relays of unload is done by each SLAVE controlling the continuous unload of the corresponding compressor.
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Service Manual – Preliminary Version
MicroTech II Control
Forced Unloading
Used inputs:
•
Outlet Temperature (B2)
•
High pressure (B7)
Used Parameters:
•
Prevent Threshold of high temperature on discharge
•
High pressure Threshold
•
High pressure Differential
•
Antifreeze temperature Threshold
•
Antifreeze Differential
Used Outputs
•
Unload Solenoids
Principles of working :
Forced unload avoids the compressor to reach conditions of pressure able to lock it in alarm condition. Compressor is forced to unload when :
• high pressure threshold is reached
• antifreeze temperature threshold is reached.
Hold Phase (hold pressure: standby of compr. by high pressure)
During compressor load if pressure reaches a reference value (pprevent), selectable by keypad under manufacturer psw, controller holds compressor
at the load currently reached.
N.B.: that situation is not an alarm, not even a warning, thus no message will appear on the display, but a symbol will be displayed for Service
personnel (see mask information for further details) .
Decrease Phase (unloading pressure: pressure warning)
If pressure, in spite of the phase of hold pressure, is still increasing until a new reference value (pwarning), selectable by keypad under manufacturer
psw, controller will force compressor to unload until a pressure value (pwarning - diff.) will be reached. Also diff is keypad selectable in the same mask
of pwarning, under manufacturer psw.
N.B.: that situation is a warning, not an alarm, thus no message will appear on the display, but a symbol will be displayed for Service personnel
(see mask information for further details) .
High pressure Phase (high pressure)
When reached the high pressure value, selectable by keypad under manufacturer psw, controller goes in alarm , stops compressor without
pumpdown and sends a message of alarm on the display.
Logic is described on the following graphics:
high pressure threshold
Differential
Differential
Release 1.0 01/05/01
antifreeze temp threshold
High pressure
Outlet Temperature
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Service Manual – Preliminary Version
MicroTech II Control
Start-up of a single compressor
Used inputs:
• Thermostat (inlet temperature)
Used Parameters:
• Delay time to start.
Used Outputs:
• Fan group.
• Liquid solenoid Valve.
• Compressor.
Description of the logic :
Start phases are described in the following graphic :
THERMOSTAT
LIQUID SOLENOID
FAN GROUP
COMPRESSOR
Delay to Start
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MicroTech II Control
Start of the compressor motor
Used Inputs:
• Inlet Temperature
Used Parameters:
• Time between star and line
• Star pulse duration
• Time between star and delta
Outputs used :
• Contactor Line
• Contactor Star
• Contactor Delta
Description of the Logic:
Motor star is described in the following diagram :
Contactor
Line
Contactor
Star
Contactor
Delta
Time between star
and delta
Time between
Line and star
Star Duration
Limitations at compressor start
Two kind of limitations at the start are considered, both allow compressor to start with delta contactor by-passing star contactor. Enabling is the
same for both in the following cases:
1. When specific values for high and low pressure are over, selectable by mask.
2. When threshold of equalized pressure is over, selectable by mask. In the software this pressure is the average between low and high pressure.
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Service Manual – Preliminary Version
MicroTech II Control
PUMP-DOWN Management
Pump-down function is executed at compressor shutdown.
It ends due to the low pressure switch or, in case this faults, for maximal time.
Pumpdown
Used Inputs:
•
Low pressure transducer
Used Parameters:
•
Pump-down type
•
Pump-down enabling by switch with unit off
•
Pump-down Setpoint in fix mode (disabling)
•
Pump-down MaxTime
Used Outputs:
•
Liquid Solenoid Valve
If enabled, pump-down arrives either when compressor stops by logic either when unit is stopped by ON/OFF switch.
Its time is selectable and it can end for max time or by pressure switch.
In case of alarm stopping the unit or the compressor, pump-down ends immediately.
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Service Manual – Preliminary Version
MicroTech II Control
Compressor Rotation
The compressor-call rotation causes the hour number and the start-stop number of different compressors to be equivalent. Rotation is carried out
according to a FIFO-type logic; this means that the first compressor to start will be the first to stop. As a consequence of this behaviour, remarkable
differences could occur in the initial phase as regards the working hours of the various compressors, but at full working such differences will
increasingly attenuate. The rotation only involves the compressors , not the capacity controls. Compressor rotation can be disabled using the
appropriate parameter.
Management without rotation:
• Start: C1,C2,C3,C4,C5,C6,...,C16.
• Stop : C16,C15,C14,C13,C12,C11,...,C1.
Management with FIFO rotation (the first compressor to start will be the first to stop):
• Start: C1,C2,C3,C4,C5,C6,....C16.
• Stop: C1,C2,C3,C4,C5,.....C16.
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Service Manual – Preliminary Version
MicroTech II Control
Condensation regulation
Condensation can be carried out as follows:
• on/off bound to the compressor working ( without the pressure transducers)
• on/off or modulating bound to the reading of the pressure transducer (if the high-pressure transducers have been enabled)
• on/off or modulating bound to the reading of the battery 1 and 2 temperature probes 1 and 2 (if the battery temperature probes have been
enabled)
Used inputs:
• high pressure probe C1 B7
• high pressure probe C2 B8
• battery temperature probe C1 B3
• battery temperature probe C2 B4
Used outputs:
• Fan 1
• Fan 2
• Fan 3
• C1 AOUT1 fan speed regulation
• C2 AOUT2 fan speed regulation
Used parameters:
• Condensation control selection: none/pressure/temperature
• Type of condensation battery (Single / Separated)
• Condensation Set-Point
• Condensation Band
• Number of fans for battery
• Prevent function enabling
• Prevent threshold
• Prevent differential
• Output voltage relevant to the inverter minimum speed
• Output voltage relevant to the inverter maximum speed
• Speed-up time inverter
On/off condensation connected to the compressor working:
With this type of condensation the fan working will be subordinated solely to the compressor working:
Stopped compressor = stopped fan
Started compressor = started fan
On/off condensation connected to the temperature or pressure sensor:
With this type of condensation the fan working will be subordinated solely to the compressor working and to the value read by the pressure or
temperature sensors as a function of a set and of a band. When the pressure/temperature will be lower or equal to the set, all the fans will be
stopped; when the pressure/temperature increases up to set + band, all the fans will be started.
It will be possible to select condensation with single battery or with separated battery; with the single-battery condensation, the fans will be
controlled by the higher pressure/temperature; with the separated -battery condensation, each sensor of pressure/temperature controls its own fan.
Modulating condensation connected to the pressure or temperature sensor:
With this type of condensation the fan control will be carried out through a 0/10 V analog output proportional to the request of the pressure/
temperature sensors. Also in this case it will be possible to select condensation with single battery or with separated batteries. Control will be
identical with the above one. If the lower limit of the ramp is greater than 0V, we will not have a proportional straight line but, as in the first part of
the graph, one step below the dif. Set-Point.
10 Volt
0 Volt
Setpoint
1bar
band
Prevent
Threshold
Alarm
high pressure
batt. temperature
Prevent Function:
That function selectable under Manufacturer password, is to avoid the circuits stop for high pressure.
When this threshold is reached with compressor on, compressor is forced to unload until the pressure falls down the setpoint - a selectable
differential.
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Service Manual – Preliminary Version
MicroTech II Control
When this threshold is reached with compressor on, fans are forced on until the pressure falls down the setpoint - a selectable differential.
Condensation Control with cut enabling
This logic is applied to the units where the continuous speed control is requested to allow the unit to work with a reduce noise level. In those units it
is needed to limit the number of spins of the fans until an assigned pressure of condensation. Whenever the pressure of condensation goes over
the allowed limit, controller will release the maximum signal speeding up fans until the maximum regime of rotation.
Here below a table explaining the graphic following:
Pos.
A
MicroTech II Reference
Inverter Setpoint
B-A
Inverter Differential
C
Point shutdown fans
D
Point insertion
E-B
Hysteresis
F
Cut
G
Set high pressure switch
Description
Value of pressure the controller is releasing no proportional signal (reference = 0
Vdc)
Differential Value the controller is releasing the maximum proportional signal
(reference = 10 vdc). That value, added to the value of the point A, gives the
pressure of max rotation speed for the fans.
Point of transition for the relay of the 1° fan of each circuit for disabling the work
of the fan speed regulator (fans off).
Point of transition for the relay of the 1° fan of each circuit for the work of the fan
speed regulator (fans on).
This value of differential pressure, added to the value of the point B, gives the
pressure where fan speed changes(maximum signal).
Refers to the maximum proportional signal released by the controller during the
control of the rotation speed of the fans.
Set Point of the high pressure switch
Volt
F
A
C
D
B
E
bar
In the case a regulation with cut enabling is not requested, to have a simple continuous fan regulation based on a proportional signal following the
condensation pressure set as follows under Manufacturer psw points B,E,F:
• F = 10 Volts
• B=E xx.x bar
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page 16/16
Service Manual – Preliminary Version
MicroTech II Control
Antifreeze regulation
Used inputs
• Output temperature probe
Used parameters:
• output probe enabling
• antifreeze heater Set-Point
• antifreeze heater differential
• antifreeze alarm Set-Point
• antifreeze alarm differential
Used outputs:
• antifreeze heater
Each MicroTech II unit can manage the antifreeze regulation provided that the output temperature probe is connected and enabled.
Antifreeze heater
activation
Antifreeze alarm activation
Heater diff.
Antifreeze diff.
Antifreeze set
Heater Set
The antifreeze regulation is always energized also when the machine is OFF, both summer working and winter working.
Note : the antifreeze alarm on any MicroTech II unit stops the entire machine.
Release 1.0 01/05/01
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Service Manual – Preliminary Version
MicroTech II Control
Electro-valve Management
This software is configured to handle only the
Electro-valve liquid-injection
Used Inputs:
Discharge Temperature B4
Used Parameters:
Enabling threshold electro-valve
differential electro-valve
Inihibited Outputs:
Economizer solenoid Valve, oil-cooler, liquid-injection
Working Description
Electro-valves are activated based on the discharge temperature of the compressor, as showed in the graphic:
Enabling threshold
alarm by pressing
(120 ºC)
Differential (10 ºC)
Release 1.0 01/05/01
Enabling threshold electro-valve:
Liquid injection (85 ºC)
Diff. (5 ºC)
Discharge
temperature of the
compressor
page 18/18
Service Manual – Preliminary Version
MicroTech II Control
Regulation on water/water units chiller only
Used inputs :
• Evaporator Inlet Temperature
• Evaporator Outlet Temperature
• Condenser Inlet Temperature
• Condenser Outlet Temperature
Used Outputs
• Compressors
• Digital Output n°6 for solenoid 1
• Digital Output n°7 for solenoid 2
Used Parameters:
• Unit type
Special features of working:
1. Water Pressure Control
2. Tower Control on Condenser Line
3. Three Way Valve Control on Condenser Line
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Service Manual – Preliminary Version
MicroTech II Control
Water pressure control for PFS units
Used Inputs:
•
•
Used Parameters:
•
•
Used Outputs:
•
•
•
condenser inlet water temperature
evaporator inlet water temperature.
Setpoint of First Opening in Cold Start
Setpoint of High Discharge Superheat
Driver EXV8 Valve
Compressor Output
Liquid injection solenoid
Cold
Start
(WPC)
Pre-Start
Cold Start
Normal
Start (PI)
1.6
Valve
Closing
Dead Band
2.1
Reverse to
WPC
Valve
Opening
2.3
Normal
Logic (PI)
On Working
2.0
Pre-start:
Input values are converted in pressure based on the internal pressure/temperature table.
•
If the ratio of these pressures is upper than 1,6 the controller will start compressors following the normal start procedure.
•
If the ratio is lower than 1,6 the controller will start compressors following a logic of “cold” start.
Cold Start:
Controller opens the expansion valve at 20% (value selectable by keypad) and it starts compressor. Instead of controlling the superheat, MicroTech
II checks for compression ratio (absolute discharge pressure / absolute evaporation pressure) opening or closing the expansion valve to maintain
that ratio between 2.1 and 2.3. If that ratio goes down 2.1 controller closes the valve, if the ratio goes over 2.3 opens it. Between these values the
valve will remain steady (dead band).
During the WPC superheat and subcooling will reach very high values but they will be ignored (there is no alarm of low/ high superheat).
While evaporator and condenser water temperatures approach design conditions, the value of suction superheat decreases continuously. Cold start
can be considered at the end when suction superheat reaches 2°C. A this point control is left to the Alco driver targeting suction superheat around
0,5°C.
During cold start the following anomalous conditions can happen:
1. Low suction pressure:
If electronic expansion valve closes excessively, to ensure the minimum compression ratio, it is possible the
suction pressure goes down the freeze value. In that case controller will reduce load of the compressor/s until the suction pressure will come
back at least at 0°C. In case that situation is not verified, after 120 sec. the controller will shut down 1 compressor in alarm of low pressure. if
after this the pressure will remain lower than zero, after further 120 seconds it will stop in alarm also the second compressor. The time of
delay will be only 40 seconds if low pressure is equivalent to –10°C.
2. High condenser pressure: During that control it can happen that excessive refrigerant fill the condenser dramatically reducing the exchange
surface. In that condition condenser pressure could increase over the maximum allowed. If so, controller will unload following the logic of the
pressure of condensation.
3. High discharge superheat: Closing the expansion valve, saturated suction temperature will reduce and of course suction superheat will
increase. As a reaction, also discharge superheat will increase. If during the WPC discharge temperature should reach the selected value of
85°C (selectable value), the controller will active a procedure for cooling oil, by enabling the output for the liquid injection solenoid. If
Release 1.0 01/05/01
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Service Manual – Preliminary Version
MicroTech II Control
discharge temperature will keep in going up, controller will stop at 95°C in alarm the corresponding compressor. If otherwise temperature will
go down, the controller will disable the liquid injection when that temperature will be lower than the setpoint minus the selected differential.
On working:
It can happen that on working temperature of cooling water will decrease excessively for example due to an anomalous control of the cooling tower.
In this case the compression ratio could go down the minimum limit of 2.0.
The controller will react by controlling the compression ratio as previously described.
Compression ratio will be controlled back between 2.1 and 2.3 playing on the control of the expansion valve.
Release 1.0 01/05/01
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Service Manual – Preliminary Version
MicroTech II Control
Control Logic of the cooling tower for PFS
PFS with single compressor:
Used Inputs
•
Used Parameters
•
•
•
Used Outputs
•
•
•
Condenser inlet water Temperature
Setpoint Insertion Tower Steps
Insertion Differential
Number of Available Tower Steps
First Step Cooling Tower OD12
Second Step Cooling Tower OD13
Third Step Cooling Tower OD08
Control logic must be proportional to the input in the following way:
•
One step control:
the first relay is enabled when reached the value of setpoint + the differential. The relay is disabled when
temperature goes down the setpoint (es. Spt= 30°C ÷ Diff.= 5°C ÷ Tecc.= 35°C ÷ Tdisecc.= 29,9°C)
on
off
Stp
•
Stp+diff
Two steps Control:
The first relay is enabled when reached the value of setpoint + half differential. The second step is enabled when
reached the value of setpoint + the differential. Steps will be disabled as per the following schematic:
on
1° Step
off
Stp
Stp+1/2diff
on
2° Step
•
off
Stp
Stp+diff.
Three steps Control: The first relay is enabled when reached the value of the Setpoint + 1/3 of the differential. The second step is enabled
when reached the value of Setpoint + 2/3 of the differential. The third step is enabled when reached the value of Setpoint + the differential.
Steps will be disabled as per the following schematic:
on
1° Step
off
Spt + 1/3 diff
on
2° Step
off
Spt + 2/3 diff
on
3° Step
off
Spt
Spt + 1/3 diff
N.B: the number of steps controlling the cooling tower is selectable by keypad under “User” password.
Release 1.0 01/05/01
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Service Manual – Preliminary Version
MicroTech II Control
PFS with two Compressors:
Used Inputs
•
Used Parameters
•
•
•
Used Outputs
•
•
•
Condenser inlet water Temperature
Setpoint Insertion Tower Steps
Insertion Differential
Number of Available Tower Steps
First Step Cooling Tower OD12
Second Step Cooling Tower OD13
Third Step Cooling Tower OD08
Units with two compressors install two MicroTech II cards connected in network. Each card owns three digital outputs for tower control. Thus the
maximum number of steps is six.
Control logic is similar to the three steps control, as previously specified. In the case is requested to enable from 4 to 6 steps, the three digital
outputs OD12, OD13 and OD08 of the SLAVE card will be enabled.
Control logic is as previously specified.
Differential is divided per the number of steps (selectable by keypad). Each step is inserted based on the temperature of the inlet water reaching
the value of Spt + diff/n°grad.
Control Logic of the 3-way valve for PFS units
Used Inputs
•
Used Parameters
•
•
Used Outputs
•
Condenser inlet water Temperature
Setpoint on Condenser Temperature on the zero voltage scale
Differential of Full Scale
Analog Signal of Control Valve 0-10V Y0
The control system of the cooling water on the condenser can be done also by a three way bypass valve.
That valve, installed by the Customer, can be controlled through a 0-10V analog signal from the output Y0 of the MASTER card.
By keypad it is possible to introduce the Setpoint of condenser return water temperature corresponding to an output of 0 volt. More, a temperature
differential has to be settled corresponding to a signal of 10 volt.
To set the valve, a percentage of minimum valve opening has to be selected (es. 10% corresponding to 1 volt output) and a percentage of
maximum valve opening (es. 90% corresponding to 9 volt output).
Logic is similar to that of the inverter control on air cooled units.
10 V (100%)
% Max valve opening
(keypad selectable)
% Min valve opening
(keypad selectable)
0 V (0%)
Stp (°C)
Release 1.0 01/05/01
Stp + Diff. (°C)
page 23/23
Service Manual – Preliminary Version
MicroTech II Control
ALARMS
General description
The alarms will be divided into three categories :
• Only signalling alarms (only display and buzzer signalling, signalling on display, buzzer, alarm relay)
• Circuit alarms (deactivate only the relative circuit, signalling on display, buzzer, alarm relay)
• Serious alarm (deactivates the entire system , signalling on display, buzzer, alarm relay)
Only signalling alarms
•
•
•
•
•
Unit maintenance alarm
Compressor maintenance alarm
Damaged or disconnected clock card alarm
Mains-disconnected unit alarm
Driver alarms: driver high pressure, super-heat and absence of valve closing during the last stop (“not closed valve during stop”)
•
•
•
•
•
•
•
•
•
•
High pressure/press. contr. alarm
Lowe pressure alarm
Compressor thermal alarm
Oil differential alarm
Fan thermal alarm
Driver – probe error alarm
Driver - motor error alarm
Driver - eeprom error alarm
Driver - battery malfunct. alarm
Driver – low pressure alarm
•
•
•
Water flow failure alarm
digital outlet delayed at the start and at full function
Evaporator antifreeze alarm probe function in evaporator outlet with operation set and reset differential, with manual reset
Digital input serious alarm unit immediate stop with manual reset
Circuit alarm
Serious alarms
immediate compressor stop with manual reset
delayed at the compressor start immediate full function manual reset
immediate compressor stop with manual reset
delayed at the acquisition with manual reset
immediate fan stop with manual reset
stop compressor/s of the relative circuit
stop compressor/s of the relative circuit
stop compressor/s of the relative circuit
stop compressor/s of the relative circuit (can be enabled)
stop compressor/s of the relative circuit (can be enabled and delayed)
The reset of the alarms is executed by pressing twice the alarm button.
No driver alarm is of the serious type.
Alarm historical
If you use the clock card having the MICROTECH IICLKMEM0 code with eeprom 32K, it will be possible to have a historical of the last 900 alarms
being occurred. There are two masks of the alarm historical : one which displays the chiller parameters (setpoint, band, inlet temperature and
outlet temperature) stored when an alarm occurs and another one that displays the driver parameters (superheat, pressure, temperature and valve
position) stored as soon as an alarm takes place.
For each alarm it is possible to store
Mask 1 (CHILLER):
• Code of the activated alarm
• Date and hour of the activation
• Regulation setpoint
• Regulation band
• Inlet temperature
• Outlet temperature
Mask 2 (DRIVER):
• Code of the activated alarm
• Date and hour of the activation
• Super-heat temperature
• Valve position (in “steps”)
• Pressure from driver
• Temperature from driver
The data of this historical remain stored in the eeprom of the above mentioned card.
Release 1.0 01/05/01
page 24/24
Service Manual – Preliminary Version
MicroTech II Control
Alarm table
Code
Alarm Description
Compressor
Off
Fan
Off
Pump
Off
System
Off
Reset
(auto/man)
Delay
Enabling
AL01
CHILLER
Severe alarm
*
*
*
*
man
no
AL02
Antifreeze alarm
*
*
*
AL03
AL04
AL05
Evaporator pump thermal
Condenser pump thermal
Evaporator flow control
*
*
*
*
*
*
man
or no
auto.
(default is
“manual”)
man
no
man
no
man
selectable
enabling
both
on
master and slave
resetting mode can be
set by user
AL06
AL10
AL11
AL12
AL13
AL14
AL15
AL16
AL17
AL20
AL21
AL22
AL23
AL24
AL30
AL31
AL32
AL33
AL34
AL35
AL36
AL37
AL40
AL41
AL42
AL50
AL51
AL54
AL55
Condenser flow control
Low-pressure pressure switch 1
Low-pressure pressure switch 2
High-pressure pressure switch 1
High-pressure pressure switch 2
Oil-differential pressure switch 1
Oil-differential pressure switch 2
Compressor 1 thermal
Compressor 2 thermal
Fan 1 thermal
Fan 2 thermal
Fan 3 thermal
High press. transducer 1
High press. transducer 2
Damaged probe B1
Damaged probe B2
Damaged probe B3
Damaged probe B4
Damaged probe B5
Damaged probe B6
Damaged probe B7
Damaged probe B8
Pump maintenance
Compressor 1 maintenance
Compressor 2 maintenance
Offline unit 1
Offline unit 2
Evaporator fan thermal
Damaged 32k clock card
DRIVER 1
Driver1 – Probe error
Driver1 – Step motor error
Driver1 – Eeprom error
Driver1 – Battery error
Driver1 – High pressure
Driver1 – Low pressure
Driver1 – Super-Heat
Driver1 – Valve not closed during stop
Driver1 – wait for valve reopening
Driver1 – wait for battery recharge
Driver1 – wait for eeprom restart
DRIVER 2
Driver2 – Probe error
Driver2 – Step motor error
Driver2 – Eeprom error
Driver2 – Battery error
Driver2 – High pressure
Driver2 – Low pressure
Driver2 – Super-Heat
Driver2 – Valve not closed during stop
Driver2 - wait for valve reopening
Driver2 - wait for battery recharge
Driver2 - wait for eeprom restart
*
*Circuit 1
*Circuit 2
*Circuit 1
*Circuit 2
*Circuit 1
*Circuit 2
*Comp. 1
*Comp. 2
*
AL60
AL61
AL62
AL63
AL64
AL65
AL66
AL67
AL68
AL69
AL70
AL80
AL81
AL82
AL83
AL84
AL85
AL86
AL87
AL88
AL89
AL90
Release 1.0 01/05/01
*Circuit 1
*Circuit 2
*
*
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
* Circuit
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
man
man
man
man
man
man
man
man
man
man
man
man
man
man
auto.
auto.
auto.
auto.
auto.
auto.
auto.
auto.
man
man..
man.
auto.
auto.
man.
man.
selectable
selectable
selectable
no
no
selectable
selectable
no
no
no
no
no
no
no
60 sec.
60 sec.
60 sec.
60 sec.
60 sec.
60 sec.
60 sec.
60 sec.
man.
man.
man.
man.
man.
man.
man.
man.
man.
man.
man.
selectable
man.
man.
man.
man.
man.
man.
man.
man.
man.
man.
man.
selectable
enabling
both
master and slave
on
30 sec.
30 sec.
selectable
selectable
selectable
selectable
selectable
selectable
selectable
selectable
selectable
selectable
Enabling
Enabling
Enabling
Enabling
page 25/25
Service Manual – Preliminary Version
MicroTech II Control
Driver alarms
The alarms coming from the driver cards also report the indication of the driver that has generated the alarm (in the example : “D:3”)
Example:
m_Drv_AL60
+--------------------+
¦AL:066
D:3 U:2¦
¦ Superheat alarm
¦
¦
¦
¦
¦
+--------------------+
When an alarm mask appears relative to the driver card, above left the writing “Driver” appears, furthermore, on the right “D :” indicates the driver
whilst “U :” indicates the MicroTech II card connected to the driver indicated.
In the example, the alarm comes from the driver no. 3 which is connected via pLAN to the MicroTech II card no. 2. This numeration is relative to the
allo connection diagram explained above and successively proposed again.
thermoregulation probe of
all the system
MicroTech II MicroTech II
1
2
(Master)
(Slave)
EXV 1
EXV 2
EXV 3
EXV 4
Driver 1
Driver 2
Driver 3
Driver 4
Terminal
LCD (4x20)
Short summary of the driver card alarms
•
•
•
•
•
•
•
•
•
•
•
probe error (malfunctioning or failure of the temperature and/or pressure probe)
step motor error (valve motor connection damage)
eeprom error (writing or reading eeprom malfunction)
battery error (battery malfunction)
high pressure on the EXV driver (the operating pressure has exceeded the MOP max. threshold)
low pressure on the EXV driver (the operating pressure has exceeded the LOP min. threshold)
superheat alarm
valve not closed during stop (valve not completely closed after the last blackout)
I wait for valve reopening (warning! I wait for valve complete closing in order to restart correctly)
I wait for battery recharge (warning! I wait for battery recharge)
I wait for eeprom restart (warning! I wait for eeprom restart)
(See the mask list at the end of the manual for more information).
Furthermore, it is possible to stop the circuit compressor/s when the relative driver reports the alarm “battery error” and/or “low pressure mode for
EXV driver” (LOP mode). It is also possible to enter a delay for the last alarm (the default is : alarm enabled with a 0 second delay).
m_manuf_246_Drv
+--------------------+
¦Driver
alarms ¦
¦Stop driver 2
¦
¦compressors if in ¦
¦err. of battery
N¦
+--------------------+
Release 1.0 01/05/01
page 26/26
Service Manual – Preliminary Version
MicroTech II Control
pLAN network
All the devices connected to the pLAN network are identified through their own address.
If the same address is assigned to several units, the network can not operate.
Since terminals and MicroTech II I/O cards utilise the same type of addressing, terminals and MicroTech II cards with the same identifier cannot
exist.
The values selectable for the address range from 1 to 16 as to the terminals and from 1 to 16 with regard to the I/O cards. The overall number of
peripherals that can be connected t the network is 16.
Actually, maximum combinations can be:
8 terminals
+
8 I/O cards
1 terminal
+
15 I/O cards etc.
The addresses are set up for the terminals through the dipswitches placed on the back, whereas for the I/O cards the network-option card is
required.
I/O card address
Network-option card (MICROTECH IIADR0000 / MICROTECH IICLKMEM0)
The network-option card is available in two versions:
only dipswitch and LED
Cod.: MICROTECH IIADR0000
dipswitch, LED and calendar clock
Cod.: MICROTECH IICLKMEM0
Such card is indispensable for the network operation of the MicroTech II I/O cards, also if only one MicroTech II board is used.
The following table reports dipswitch codify for pLAN address from 1 to 16.
Adr
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Sw1
ON
off
ON
off
ON
off
ON
off
ON
off
ON
off
ON
off
ON
off
Off
On
Sw2
off
ON
ON
off
off
ON
ON
off
off
ON
ON
off
off
ON
ON
off
Sw3
off
off
off
ON
ON
ON
ON
off
off
off
off
ON
ON
ON
ON
off
Sw4
off
off
off
off
off
off
off
ON
ON
ON
ON
ON
ON
ON
ON
off
Sw5
off
off
off
off
off
off
off
off
off
off
off
off
off
off
off
ON
R G V
Sw1
Sw2
Sw3
Sw4
Sw5
In the standard application EPSTDEMCHA modular chiller addresses for the MicroTech II units:
1
2
3
Unit no.1
Unit no.2
Unit no.3
Release 1.0 01/05/01
4
Unit no.4
page 27/27
Service Manual – Preliminary Version
MicroTech II Control
Terminal address
Terminal card viewed from behind
Microprocessore
On
Off
Dip-switch
Conn.
Conn.
stampante
rete locale
1 2 3 4 5 6 7 8
The address of the terminals is set up through the dipswitch bench found on the back . The address is selectable in the 1-16 range by utilising the
1-5 dipswitch. The address value is obtained via the following table (see also previous paragraph):
The terminal of the 4 relay MicroTech II units must have an address greater than 5.
Unit terminal
n.: 1,2,3,4.
Address 5 dip-switches
5
Terminal management
•
•
•
•
•
Each MicroTech II card, connected to the network, can manage several terminals (max. 3). The display on them occurs simultaneously and not
independently, it the same thing as having keypads and displays connected in parallel.
Each terminal associated to a certain card can be private or shared.
A terminal is said to be private if it displays exclusively the output of an I/O card.
A terminal is said to be shared if, automatically or through keypad, may be switched between several control cards.
Each MicroTech II keeps constantly updated the display of the private terminals; on the contrary, if a shared terminal exists, the latter will be
updated only if the involved MicroTech II have presently its control. From the logical point of view the following diagram is valid:
PRIVATE
PRIVATE
Privato
Privato
MicroTech
PcO
II
MicroTech
PcO
II
1
3
SHARED
Condiviso
MicroTech
PcO
II
2
•
•
PRIVATE
Privato
PRIVATE
Privato
MicroTech
PcO
II
4
In the example the shared terminal is associated with 4 I/O cards but, in the example, only the 2 can display data and receive keypad
commands from it . The switching between cards takes place, in a cyclic sequence (1→2→3→4→1....), by pressing the button (or a
combination of two) to which this function has been assigned.
The communication can also occur automatically upon direct request of the program. For instance, a I/O card can request the control of the
shared to display alarms or, on the contrary, give it to the following one at a precise established time (cyclic rotation).
Release 1.0 01/05/01
page 28/28
Service Manual – Preliminary Version
MicroTech II Control
The number and type of terminals is established during the initial network configuration. The relevant data are stored in the EEPROM
memory of each single I/O card.
Terminal configuration procedure
• The first operation to be performed, when for the fist time a pLAN network is to be started or an I/O is replaced, is the activation of the terminal
configuration procedure.
• Before beginning such procedure make sure that each I/O card and each terminal has been given the correct address during the network
design. It is important to remember that the address being set up through the dipswitches is received only if a reset of the device is carried out.
Furthermore, you should to carry out a global resetting of all the network devices if you realise that you have chosen the wrong configuration of
the addresses (several cards with the same address).
• The configuration procedure has to be activated for each I/O card and must involve all the network terminals. Such procedure can be activated
from any terminal, which can also have been timerarily connected only to carry out the configuration operations and removed when finished.
•
The operations to be done are the following:
Step 1: I/O card selection
•
•
The procedure is activated by pressing simultaneously the 0-1-2 buttons for at least 5 sec. (for compatibility, also the 56-Enter buttons carry
out the same function):
T0
T1
T2
T8
T9
T 10
T3
T4
T11
T12
On-Off
Alarm
T6
T14
Up
T5
T15
Down
T13
Enter
If the display is of the LCD type, the following mask is displayed:
Terminal Adr: nn
I/O Board Adr: 12
•
•
•
•
The Terminal Adr field fixed and represents the address of the terminal on which you are operating, set up through the posterior dipswitch.
The I/O Board Adr field at first displays the address of the MicroTech II card actually connected to the terminal. If the terminal is not connected
to any MicroTech II card the '--' characters are shown. Through the arrow-buttons it is possible to modify such selection in order to force the
connection to another controller. The values displayed during the selection are the addresses of the MicroTech II cards actually being
connected to network. If no MicroTech II at the moment is active, it is not possible to change the '--' display.
By pressing the Enter button you get out of the first phase of the procedure, which resides in the terminal, and you enter the real terminal
configuration mask, see step 2.
If the terminal remains inactive (no button pressed) for more than 15 seconds, it automatically leaves the configuration procedure.
Step 2: selection of the associated terminals
For LCD displays the displayed masks are:
Terminal Config
Press ENTER
to continue
Enter
⇓
P:12
Trm1
Trm2
Trm3
•
Adr
02
03
None
Priv/Shared
Sh
Pr
-- Ok? No
In this mask the Enter button moves the cursor from one field to another whereas the arrow-buttons change the current value of the field. The
P:12 symbol in this case indicates that the I/O address-12 card has been selected .
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Service Manual – Preliminary Version
•
MicroTech II Control
To leave the configuration procedure and store, select the 'Ok ? no' field and with the cursor buttons until 'Yes' appears and then press Enter.
To get out without storing, it is necessary to wait for 30 sec without pressing any button.
Display of the terminal connection state
• If the terminal shows the state of inactivity of the CPU card of which it is displaying the output, clears completely the display and shows the
message:
I/O Board xx fault
•
If the terminal does not receive the message of network synchronisation (token) for more than 10 sec, it clears completely the display and
scows the message:
NO LINK
•
this is equivalent to the condition of OFF green LED for the I/O cards.
Display of the network state: NetSTAT
•
•
In the program there is a procedure, can be activated only in the LCD version, that allows the display in real time the state and type of the
peripherals actually being connected.
Such procedure is activated by the simultaneous pressure of the 0-1-2 buttons (or else Up-Down-Enter) for at least 10 sec. (after the elapse of
the first 5 sec you obviously enter the terminal configuration procedure). The mask displayed is the following:
NetSTAT 1
9
T: xx
17
Enter
To Exit 25
•
•
8
16
24
32
The number after T: indicates the address of the terminal on which the procedure is activated, the symbols indicate the type of peripheral
(terminal/MicroTech II) and the respective address.
In the example the network turns out to be composed of MicroTech II cards with address 1, 2, and of 3 terminals with address 3, 4, 15.
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Service Manual – Preliminary Version
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MicroTech II Control
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